The present invention relates to a gymnastic device for the exercise of the back and abdominal musculature, said device comprising an elongated beam and means arranged at said beam for transferring the effects of a force between said device and its user.
So far no gymnastic device exists specifically intended for the abdomen and back. Devices intended for general gymnastics and strengthening of muscles have been used for the exercise of abdominal and back muscles. The device which is most common in home use comprises a disc bar, i.e. a bar provided with weights in both ends. It is not, however, possible to perform gymnastic movements which are ideal for the back and abdominal musculature with a disc bar.
Another gymnastic device intended for home use comprises a bar which is stressed in between two door posts. Moreover, rings or bars hanging in straps and intended for hanging in, are popular for home use. Consequently, there does exist several different devices but with the exception of one quite recently developed device, none of the known devices is in all respects suitable for exercising the important abdominal muscles and the situation is just as bad for the exercise of the back musculature. When considering that backache today is an extremely common disorder, it is surprising that no easily handled devices for back exercise exist.
A fairly new device comprises essentially a plastic board with handles provided at the sides thereof. The user lies down on said plastic board resting of the floor, and grips the handles and pulls himself up into a sitting position (so called sit-ups). The poorer the user""s abdominal muscles are, the more he is forced to use his arms for the pulling movement. However, this device is only intended for exercising the abdominal muscles.
Despite the existence of the above mentioned devices the situation is so far such that there are no suitable ways of providing a regular exercise of the back and abdominal muscles with existing devices. On the other hand, the lack of exercise of the abdominal and back musculature forms an essential part of various kinds of physiological disorders which cause considerable losses both individually and for society.
In order to have a healthy back, the abdominal muscles should also kept be in good condition. These two muscle groups co-act and support each other. It is therefore important that a suitable gymnastic device inherently combines the possibility to exercise both important entities, i.e. both the abdominal and back muscles, with one and the same device, and it should be possible to perform this exercise at home as well as in a gym. Since backache is a very common disorder, a suitable device should be developed for home use and for quite ordinary persons.
In order to exercise the abdominal muscles and the back muscles, a person must either bend his body forward (the abdominal muscles) or slightly backwards (the back muscles). In order to increase the burden it is common especially for athletes to use weights either over the breast or at the neck. The person lies on the floor or on a bench and heaves up the upper part of his body. However, weights over the neck may cause the body to bend too much backwards at the small of the back, which usually damages the back, causing e.g. vertebral disorders. On the other hand, a forward bending will cause the weight to pull the upper part of the body downwards, which in turn will cause an incorrect burden on the small of the back. It may thus be concluded that weights over the neck tend to press the body into a crooked shape. It is therefore often considered that the weight of the body itself is sufficient. In any case, a person exercising the abdomen or the back in this way will have to lie down to perform the movements, since a bending of the upper part of the body essentially lacks effect if it is performed in an upright position. Bending the upper part of the body backward and forward can even be really dangerous if the neck is loaded at the same time.
Ordinary people who for their exercise normally need movements which strengthen the back and abdominal muscles often feel that movements which are performed lying on a floor or the like feel complicated and also often too arduous, especially in case the person""s body weight is so great that it is difficult to heave the upper part of the body upwards. A common result will be that the person in question will not perform any suitable exercise at all which in the long run is very bad for the back. It is also important to have access to such devices for the exercise of the back and abdomen wherein the user of the device can perform the exercise in an upright position. Such a gymnastic device should further be simple and robust and it must not take up too much space.
The prior art patent literature disclose three devices which to some extent concern muscle exercise in an upright position. Thus, DE publication 39 15 079 relates to a device for isometric muscle exercising. Said apparatus comprises a central body having a handle-like loop means at either end. According to said patent the length of the central body may be varied, and further, the handle-like loop means may be turned in different directions. The apparatus is, however, only suitable for the performing of certain specific isometric exercises and it is not possible to perform any general constructive exercise of the back and abdominal musculature with said apparatus.
The prior art further includes U.S. Pat. No. 4,793,609 which in fact basically concerns a way of attaching a handle to an elastic beam. According to said patent the gymnastic movement at this apparatus is intended to repeatedly prolong the elastic beam by pulling at the handles. The invention described in the patent concerns an arrangement for fastening the handle to the elastic beam in such a way that the handle will not come loose during the exercise. This apparatus is not suitable for exercising the back and abdominal musculature.
The prior art further includes U.S. Pat. No. 4,925,185, as well as an earlier U.S. Pat. No. 4,834,364 concerning an essentially similar apparatus. This known gymnastic device comprises a foot plate on which the user stands. A rigid central bar is pivotally attached to said foot plate. Crossbars are arranged at said central bar on one hand at the height of the users knees and on the other hand as handles at the upper end of the apparatus. This known apparatus is used as a device for taking exercise so that the force from a muscle is transferred via said rigid central bar to act as an opposing counter force for another muscle. The essential movements which suitably can be performed with the apparatus in question are pulling with the arms on one hand, and a stretching of the thigh muscles on the other hand, said muscles being made to co-operate by the apparatus. Thus, the apparatus only has a limited utility for the exercise of the back and abdominal musculature.
The present invention provides a completely new solution to the problem of strengthening exercise of the abdominal and back musculature, and this is performed in a simple way which is well adapted to its purpose. When using the device according to the invention anybody can bend his body forward and backward standing in an upright position so that the bending takes place at the waist region. It is precisely such bending movements which are performed with the aid of the abdominal and back musculature. However, a bending movement as such without resistance has only a limited effect on the strengthening of the muscles. The device according to the present invention will now provide a possibility to add an extra resistance, which additionally may be adjusted according to the needs and capabilities of the person in question. That way the exercising movements can be utilized also as strengthening exercise.
The device according to the invention is very safe to use since it only acts in principle so as to pull the body into a straight position. This way gymnastic movements performed with the device cannot cause any damage. However, due to the fact that it is possible with the aid of the present invention to add an additional resistance, which moreover can be adjusted so as to be suitable for the person in question, it is possible for a person to exercise a his abdominal and back muscles in an ideal way and completely without risks.
The present invention is characterized by the features disclosed in the appended claims. Thus, the device suitably comprises an essentially rigid beam or body member, the rigidity of which preferably may be varied either by exchanging certain parts or through constructive details. On said body member there are arranged three suitably movable means for transferring force to the user""s body such that the lowest means acts at the foot or leg, the middle one against the trunk and the upper one at the height of the shoulders at some distance from the user""s body. The entire device will now make it possible to direct a suitably large. force against the shoulder parts of the user""s body by taking support from the waist part and from a point at the lower part of the user""s body and thus to resist a bending of his body at the waist.
Functionally the device according to the invention operates so that the user attaches his body at different points to the gymnastic device. If the beam or body member is more or less rigid a possibility for isometric gymnastics will be provided. The beam will, however, preferably be flexible to a large or small extent suitably in an adjustable way, whereby it will bend at least to some. extent under a force. The device extends longitudinally along the body from the legs to the shoulders with a support at the height of the waist. When the user now bends the upper part of his body at the waist forward or backward, the upper part of the body will act on the beam via the upper means for transferring force. For example, if the device is arranged at the back side of the user with straps around his shoulders the upper part of the body will provide a pulling of the upper part of the beam when the user bends forward. The middle means comprises a contact surface which will engage and support the small of the back. The lower means will prevent the lower part of the beam from moving freely due to its position e.g. in front of the ankle or via another fastening e.g. with straps, while the middle means take support from the waist or the small of the back. In this way the upper part of the device now will provide a resistance against the user""s bending movement forward. By adjusting the flexibility of the beam this resistance can be adjusted in accordance with the user""s needs.
Thus, the present invention has solved the problem connected with a gymnastic means with which the user can strengthen his back and abdominal musculature standing in an upright position, principally by utilizing a principle which is known per se from the acute therapy, i.e. that the body is xe2x80x9csplintedxe2x80x9d to a more or less rigid device. Each force effected by the user will be transferred to the xe2x80x9csplintxe2x80x9d. In case of a fracture of the bone or the like the purpose has been to prevent the sections of the bone from moving in relation to each other with the aid of the splint. Normal xe2x80x9csplintsxe2x80x9d do not, however, flex at a fair exertion of a force and could thus only be used for isometric gymnastics. As such isometric gymnastics is a useful method also for strengthening the back and abdominal musculature but it is often considered heavy and to some extent frustrating. The xe2x80x9csplintxe2x80x9d according to the invention is therefore arranged in such a way that, contrary to what is sought to obtain in connection e.g. with fractures, it is suitably at least slightly flexible. The xe2x80x9csplintxe2x80x9d according to the invention is preferably arranged in such a way that its elasticity or resistance to bending can be adapted in accordance with the user""s wishes.
Since the device according to the invention consists of a beam or body member which suitably is at least slightly bendable and at least three means arranged at said beam for transferring force between said member and the user""s body, a triangular force action can be formed so that one corner of the triangle can move slightly while two corners of the triangle are essentially locked at the body and prevents the whole device from twisting. Especially the upper means, which is intended for providing a force transferring contact to the user""s upper body portion, will at use suitably be slightly movable, e.g., against a spring action of the beam or body member or due to compressible support pads arranged at the middle and/or lower means. According to one embodiment the possibility for movement is provided by having flexible parts in the upper means themselves.
At use said middle means will engage the user""s trunk part and in order to make it possible to use the device in a comfortable way without the disadvantage of having a too close and thus unpleasant contact with face or back of the head or neck, said middle means is arranged in such a way that its contact surface lies substantially outside the imagined line passing between the upper and the lower means. Hereby the upper means and in any case the upper part of the beam or body member itself will be at such a distance from the body that the device will not give an unpleasant feeling even to persons with a large body. In an especially preferred embodiment of the device according to the invention this is accomplished so that the middle part of the beam or body member itself it formed as a central support surface for contacting the trunk, the beam or body member then preferably having an arcuate form.
The lower part of the user""s leg is intended in this connection to mean in the first place the shin-bone starting from the hollow angle at the ankle and ending with the hollow of the knee. Depending on whether the device is placed at the abdominal or the back side the lowest means for transferring a force will have its lowest position at the hollow angle portion above the heel and its highest position at the hollow of the knee, or its lowest position just above the foot blade and its lowest position at the hollow portion below the kneecap, respectively. The trunk part is intended to mean the user""s trunk, starting with the sit muscle and ending with the torso. Normally, said middle means engages the pit of the stomach or the small of the back, respectively. The upper part of the body, again, indicates the region from the torso upwards towards the shoulders and the arms are also counted to this region e.g. when said means comprises regular handles. In this connection it should, however, be observed that the strength in the user""s hands is generally not sufficient to provide an optimal gymnastic movement or a desired bending of the beam of the device by gripping with the hands at said upper means.
The functional principle of the present invention can in its most simple form be concluded as follows: The body is splinted to an elongated beam or body member which either bends when the body bends or resists said bending and thus provides a resistance when the user tries. to bend his body. The resistance to said bending is suitably adjustable in accordance with the user""s strength and need of exercise. In case the resistance to bending exceeds the user""s strength, an isometric gymnastic movement is provided while a small resistance provides a device for moving gymnastics.
Theoretically the idea of the present invention thus essentially comprises the feature that the upper and lower parts of the body, at a bending around the waist, should be attached to each respective part of the beam or body member, between which beam or body member parts should act a force which resists a mutual variation in the positions of said beam parts. In practice this is achieved by suitably forming the beam or body member part functionally as one single piece having a suitable resistance to bending. This is preferably performed with the aid of adjusting means which will be later described. Since a rigid attachment of said beam or body member part to the user""s body is both complicated and unpleasant, the invention is in practice suitably embodied in such a way that it consists of a rod-like means with two actual attachment means and between them a contact point which presses against the user""s trunk part. Alternatively the beam or body member may also be produced in two or more parts having between themselves a spring means for providing the desired flexibility. According to one embodiment of the invention the device can also be disassembled and/or collapsed in order to facilitate storing away or packing for a journey.
In practice the xe2x80x9csplintingxe2x80x9d will be accomplished in a variety of ways according to the invention. In order to provide suitable exercise, the number of points where the xe2x80x9csplintxe2x80x9d engages the body of the user should, however, generally be at least three, i.e. one at the lower part of the legs for locking of the beam or body member, one for engaging or supporting the user""s back or stomach and one where the user causes exertion of a force with the aid of the upper part of his body.
Said lower means is suitably a crossbar which preferably is slidably attached along the lowest part of a central beam or body member and which is supported against the legs. Alternatively, the lower means may also consist of straps or the like, pulling elements. The middle means is in turn arranged for engaging against the user""s back or stomach. This means, which is suitably somewhat widened in order to feel more comfortable, preferably consists of a crossbar or pad slidably arranged along the central middle part of the beam or body member. In use a pressure between the central beam or body member and the user""s stomach or back will act on the middle means. All of said means are suitably padded or made soft in some other way for the sake of comfort.
The upper means in turn consists of a crossbar or the like which preferably is adjustable along the height of the beam or body member and suitably being provided with straps or the like. In use the straps are put around the user""s shoulders or behind the back. In principle the said means could also comprise gripping handles, but the mere hand force is generally not sufficient for effective gymnastics. An alternative solution, on the other hand comprises yoke loops or the like which can be folded out so that they can run in the armpit and can be brought into engagement behind the arms or shoulders.
In a preferred simple embodiment of the invention the beam or body member comprises a central, somewhat bendable beam rod provided with crossbars which slide there along and which have an arcuate cross section. In said crossbars there are opposite openings wherein said central beam rod slides. The arcuate crossbars are somewhat elastic in their arcuate cross section so that they normally strive to obtain a position wherein the size or position of the openings does not exactly correspond with the cross section of the beam rod. Because of the friction between the beam and the openings said crossbars will be normally be locked to said beam rod but they can be displaced along said beam rod e.g. by pressing or pulling the cross section so that the cross sections of the openings substantially coincides with the cross section of the beam rod.